At present, the already known pulsers used in fuel pumps have some drawbacks because they are equipped with electrically supplied components which have to be installed close to the measurement point (where the convertion from a flow quantity to a number is performed) of the fuel flow which is being supplied. This means that these pulsers need to overcome strict fire-proof tests before their approval and utilization.
Furthermore, as far as the tamper-proof capabilities of the known pulser are concerned, they can be easily infringed on the transmission to a processing unit of the pulses which have been generated.
For example, the known pulsers can easily be tampered with due to the electrical-type transmission of the pulses which are generated and transmitted to a processing unit external to the pulser.
In fact, it has been often found out that is possible to introduce into the electrical transmission some additional signals. These signals are very difficult to be distinguished from the "true" signal generated by the pulser without using encryption signal processing.
Further drawbacks are the small quantity and the poor quality of the signals which can be transmitted through the electrical lines.